Trane ac

I have a Trane ac installed in my home which is about 30 years old and still very efficent. Recently, when the compressor and fan quit running, it shutters. I noticed that the fan blade does not seem to rotate freely as it slowes down. I was thinking it should rotate a little longer. Before I go out and purchase a new fan motor, am I correct in thinking it is the fan motor causing the shutter when it shuts off. I have stood there and I haven't seen the motor shake, but if you stand back away from the unit, you will see the whole unit shutter just for a second or two. No other problems with the unit that I have noticed.
Yes, I'm cheap and relying on your help.

 

I just lost my 33 year old Rheem unit. The compressor gave up ghost.

Sorry to say that shudder you see when the unit shuts off is the compressor.
You could also need a new fan motor. Try spinning the fan by hand and see how it feels.

 

PJmax - did you get complete new ac or just replaced the condenser and fan?

 

When a compressor goes bad the recovered refrigerant cannot be immediately re-used. It gets sent to a reclaimer who can then reprocess it for re-sale. However at the price of R-22.... +/- $250 a pound.... it made more sense to replace the A/C condenser and the evaporator.

Since my gas furnace was getting up there in age to I opted to change it along with the A/C.